Continuous location awareness is a highly desirable feature in modern devices. This capability is required, for example, to support location-based applications, Contextual Aware Computing and/or a multitude of Location Enabled Services (LES) applications, which require location updates, either periodic or sporadic/one time.
Various methodologies may be implemented for determining the location of a mobile device. Trilateration is a way of determining location using the locations of a plurality of other devices, generally referred to as location origins or location sources, e.g., cellular base stations, Access Points (APs), and the like.
A location estimation method may include measuring wave propagation parameters, e.g., Time of Flight (ToF) parameters, with respect to a location origin; estimating a distance between the mobile device and the location origin based on the measured parameters, and estimating a position, e.g., an absolute location, a movement, or any other position-related attribute, of the mobile device, for example, based on distances between the mobile device and a plurality of location origins, e.g., by trilateration.
Another location estimation method may be performed by a mobile device by measuring wave propagation parameters, e.g., a Time of Arrival (TOA), of signals received from two or more location sources, e.g., two APs; and estimating the location of the mobile device based on measurements and known locations of the location sources, e.g., using a hyperbolic positioning location estimation calculation. This location estimation method may be beneficial, e.g., since it may enable the location estimation without requiring the mobile device to engage in direct communication with the location sources.
The location estimation methods may not provide location estimation with a desired accuracy, for example, if one or more parameters provided by the location sources do not have a desired availability and/or accuracy.